The present invention generally relates to filtration systems for separating solid materials from liquids, and more particularly to a filtration system which incorporates multiple, rotating filter units of cylindrical design in a specialized configuration in order to provide enhanced filtration capacity.
Liquid filtration systems play an important role in a wide variety of industrial and commercial processes. In addition, high efficiency filtration systems are currently being using in numerous medical applications, including but not limited to blood filtration and the separation of microorganisms (e.g. bacteria) from biological or other fluids. In this regard, recent advances in separation technology have created filtration systems which are capable of removing solid materials of a very small size from selected liquids. Many of these systems involve the use of a sophisticated membrane structure associated with a cylindrical cartridge unit. Membrane-type cartridge units are basically described in U.S. Pat. Nos. 4,790,942; 4,867,878; 4,876,013; 4,906,379; 4,911,847; and 5,000,848. All of these references disclose single, membrane-type rotating cartridge units and/or components associated therewith.
Notwithstanding the foregoing filtration units and components, a need exists for a filtration system which is capable of removing substantial quantities of solid materials from liquids or slurries having large amounts of solids therein. Normally, when the filtration of these materials is attempted using conventional filter systems, filtration efficiency decreases substantially for numerous reasons. Primarily, the exposed surfaces of the filtration media become clogged or blocked with solid materials, thereby slowing the separation process and decreasing filter life. This situation also results in decreased filtration capacity due to a continuing need to deactivate and clean the filter system. As a result, the volume of fluid materials to be treated within a given time period is minimized. Problems of this nature typically occur in a wide variety of situations involving many types of liquid or slurry materials including but not limited to yeast slurries and beer test samples in the brewing industry, petroleum products, dairy by-products, medical compositions and the like.
The present invention represents a unique, self-cleaning filtration system which is characterized by a high degree of operating efficiency. The invention specifically involves a specialized filtration apparatus which enables the removal of solid materials from liquids having a high concentration of suspended solids therein. Also, large volumes of liquid materials may be filtered in a minimal amount of time. These goals are accomplished while avoiding the problems listed above. The present invention therefore represents an advance in the art of high efficiency filtration.